A known electrical contact for electrically connecting a connecting object to a printed circuit board, for example, is shown in FIG. 8 (see JP Registration of Design Number 1108677).
A known electrical contact 101 shown in FIG. 8 electrically connects a chassis 120 that is a connecting object to a printed circuit board 110. The known electrical contact 101 is integrally formed by stamping and forming a metal sheet, and is provided with a solder connecting portion 102 and a contact portion 104. The solder connecting portion 102 is formed into a substantially rectangular plate shape, and has a solder connecting surface 102a extending horizontal with respect to and soldered onto a printed circuit board 110. The contact portion 104 is arranged at an end of a spring region 103 extending from a back end (right end in FIG. 8) of the solder connecting portion 102. The spring region 103 includes an upstanding portion 103a standing up from the back end of the solder connecting portion 102, and an extending portion 103b extending frontward through a curved portion from an upper end of the upstanding portion 103a. The contact portion 104 protrudes upward from an end (front end) of the extending portion 103b, and is bent into a reverse U shape. The chassis 120 comes into contact with the contact portion 104 at the top thereof Then, an elongated portion 105 extends frontward from an end of the contact portion 104.
Additionally, a pair of side walls 106 extend along both side edges of the front end of the solder connecting portion 102, and a top wall 107 extends from an upper end of each side wall 106 toward a midpoint of the solder connecting portion 102. The elongated portion 105 is in contact with a lower surface of the top wall 107 to receive a preload, when the chassis 120 is not in contact with the contact portion 104. The side walls 106 and the top wall 107 prevent the elongated portion 105 from turning upward. Furthermore, the chassis 120 abutting the top wall 107 prevents an excessive stress from being applied onto the spring region 103.
Another known electrical connector is shown in FIG. 9A and FIG. 9B (see JP 2009-32440 A), which includes an electrical contact for electrically connecting a connecting object to a printed circuit board.
A known electrical connector 200 shown in FIG. 9A and FIG. 9B includes a housing 210, plural electrical contacts 220, a pair of pegs 230, and a cover 240.
Each electrical contact 220 is configured to electrically connect a battery pack (not shown) that is a connecting object to a printed circuit board (not shown) provided on a mobile phone main body. Each electrical contact 220 is integrally formed by stamping and forming a metal sheet, and is provided with a securing portion 221, a solder connecting portion 222, and a contact portion 223. The securing portion 221 extends vertical with respect to the printed circuit board, and is formed to have a U shape when viewed from the top thereof, as shown in FIG. 9A. The securing portion 221 is press-fitted and secured into slits 211 of the housing 210 from the bottom side of the housing 210. The solder connecting portion 222 is arranged at the lower edge of the securing portion 221, as shown in FIG. 9B. The solder connecting portion 222 extends parallel to the major surface of the printed circuit board from the lower edge of the securing portion 221, and is soldered and connected onto the printed circuit board. The contact portion 223 is positioned at an end of a spring region 224 through the spring region 224 extending substantially perpendicular to the securing portion 221 from a side edge of the securing portion 221. The contact portion 223 is formed into a curved shape, with which a connecting object conies into contact parallel to the major surface of the printed circuit board.
A pair of pegs 230 are provided for securing the housing 10 to the printed circuit board, and are press-fitted and secured into grooves 212 arranged on both ends of a longitudinal direction of the housing 210, respectively. In addition, the cover 240 is attached onto the housing 210 to protect the spring regions 224 of the electrical contacts 220. The contact portion 223 extends from an opening 241 arranged in the cover 240, and permits the connecting object to come into contact with the printed circuit board from the horizontal direction with respect thereto.
Furthermore, as yet another known electrical contact is shown in FIG. 10 (see JP 2004-55243 A), for electrically connecting the connecting object to the printed circuit board.
A known electrical contact 301 shown in FIG. 10 is configured to electrically connect a battery pack (not shown) that is a connecting object to a printed circuit board 340 provided on a mobile phone main body. The known electrical contact 301 is provided with a conductive cylindrical portion 310, a spring 320 positioned in a receiving space 311 of the cylindrical portion 310, and a contact pin 330. The cylindrical portion 310 extends parallel to the major surface of the printed circuit board 340. The contact pin 330 is slidably supported in the receiving space 311 of the cylindrical portion 310 and becomes conductive with the cylindrical portion 310. The contact pin 330 is biased by the spring 320 and an end portion thereof protrudes from the cylindrical portion 310. The connecting object comes into contact with the contact pin 330 parallel to the major surface of the printed circuit board 340. In addition, an outer circumference of the cylindrical portion 310 includes a plurality of connecting protrusions 312 positioned in alignment with respect to the cylindrical portion 310 and protruding in a direction intersecting with the longitudinal direction. The bottom surfaces of the connecting protrusions 312 are soldered and connected onto the printed circuit board 340. Furthermore, a holding portion 313 having a plane surface for vacuum suction is arranged on an opposite side of the connecting protrusions 312, on the outer circumference of the cylindrical portion 310.
However, in the battery connection in a mobile phone or an antenna connection in a mobile terminal called smartphone, these days, there is a need for connecting a connecting object to a printed circuit board with use of only a lone electrical contact(s) and without use of a housing. Main reasons of this need include downsizing, cost reduction, and increased variation of the contact arrangement. The increased variation of the contact arrangement means that since the use of housing makes the contacts arranged at a pitch determined by the housing, the contacts can be arranged on the printed circuit board freely, without limiting to this.
In a case where only a lone electrical contact is used without the housing, it is necessary for a component mounting apparatus to suction the lone electrical contacts when the electrical contact(s) is mounted on the printed circuit board. In addition, in reflow soldering and connecting the lone electrical contact(s) onto the printed circuit board, it is necessary for the contact to stand up by itself on the solder paste of the printed circuit hoard.
Furthermore, in the battery connection in a mobile phone, the antenna connection in a mobile terminal, and the like, these days, there is a need that the connecting object can be brought into contact with the electrical contact mounted on the printed circuit board from both of a horizontal direction and a vertical direction with respect to the printed circuit board.
It is to be noted that, however, the following problems exist in the known electrical contacts 101, 220, and 301 shown in FIG. 8 to FIG. 10.
That is, as to the known electrical contact 101 shown in FIG. 8, the upper surface of the extending portion 103b is formed to be flat and can be used as a suction surface, and simultaneously, the solder connecting portion 102 can stand up by itself on the solder paste of the printed circuit board 110. Also, as the contact point of the contact portion 104 with the chassis 120 (connecting object) faces upward, the connecting object can be brought into contact with the contact point from a vertical direction with respect to the printed circuit board. However, it is impossible to make the connecting object come into contact with the contact portion 104 from a horizontal direction with respect to the printed circuit board. This is because the pair of the side walls 106 and the top wall 107 are arranged on the front side of the contact portion 104 and they become obstacles when the connecting object passes.
Further more, as to the electrical contacts 220 shown in FIG. 9A and FIG. 9B, they are made to stand up by themselves. However, since there is no surface that can be used as a suction surface, the lone electrical contact 220 cannot be suctioned. Therefore, the upper surface of the housing 210 is used as a suction surface. Besides, although the connecting object comes into contact with the contact portion 223 from the horizontal direction with respect to the printed circuit board, the connecting object cannot come into contact from the vertical direction with respect to the printed circuit board.
Furthermore, as to the known electrical contact 301 shown in FIG. 10, it can be suctioned at the holding portion 313, and in addition, can stand up by itself on the printed circuit board 340 with the connecting protrusions 312. Moreover, the connecting object can come into contact with the contact pin 330 from the horizontal direction with respect to the printed circuit board 340. However, the connecting object cannot come into contact with the contact pin 330 from the vertical direction with respect to the printed circuit board 340. Additionally, the known electrical contact 301 shown in FIG. 10 is composed of three parts including the cylindrical portion 310, the spring 320, and the contact pin 330, whereby there are a number of parts and its costs are high. Besides, when the space 311 of the cylindrical portion 310 or the contact pin 330 is produced, a machining process is needed and its manufacturing costs are also high.